In a vehicle, the tilting or vibration, shock, etc. due to the bending or slope of the road surface, acceleration or braking, turning, etc. are transmitted to the wheels (axles) in various directions. Most vehicles are equipped with a shock absorber to prevent such tilting or vibration or shock from being transmitted to the vehicle body and passengers even if the wheels are applied with the same, thereby improving the ride comfort and allowing the vehicle to be stably controlled.
The shock absorber is composed of a combination of a cylinder (a shock absorber) filled with oil or gas and a coil spring encompassing the cylinder. Among the components constituting the shock absorber, there are a bumper stopper for coping with the impact of the cylinder, a dust cover for protecting the cylinder from dust or foreign materials, etc.
Conventionally, the bumper stopper and the dust cover have been separately manufactured and then installed in the shock absorber. However, in the case where the bumper stopper and the dust cover are separately manufactured, not only the cost of preparing the components increases, but also problems of an increase in cost and the like occur due to the increase in manufacturing process of the shock absorber.
In order to solve the problems resulted from the separate manufacture of the bumper stopper and the dust cover, a bumper stopper including a dust cover integrated in the bumper stopper has been proposed and used in the shock absorbers of lots of vehicles.
FIG. 1 shows a cross-sectional view for illustrating a state, in which a conventional bumper stopper 1 with an integrated dust cover 4 is installed on a shock absorber 5. As shown in FIG. 1, the bumper stopper 1 is constructed such that the dust cover 4 is integrated by connecting the buffer member 2 of the bumper stopper 1 and the dust cover 4 by a connection plate 3
The bumper stopper 1 constructed as above is mounted between a spring retainer 7 and a spring seat 8 in the shock absorber 5, wherein the rod L of a cylinder C passing through the buffer member 2 is fixed to a mount bracket 6 and the upper end portion of the cylinder C is inserted to be installed through the lower end portion of the dust cover 4, thereby forming the shock absorber 5.
If a vehicle with the shock absorber 5 is tilted or vibration or shock occurs while the vehicle is running, the cylinder C and rod L of the shock absorber 5 shrinks and the upper end of the cylinder C comes into contact with the inner surface of the connection plate 3 of the bumper stopper 1, (see FIG. 3) the buffer member 2 formed at the upper portion of the connection plate 2 is contracted due to the contact between the cylinder C and the connection plate 2, and in this process, the inner space of the buffer member 20 is kept closed by the upper end portion of the cylinder C.
The buffer member 2 of the bumper stopper 1 installed in the shock absorber 5 shrinks and prevents the cylinder C from operating over a limited range while preventing the shock from being applied to the cylinder C, wherein if a load applied to the shock absorber 5 increases, the shrinkage of the buffer member 2 and the force exerted by the upper end of the cylinder C on the inner surface of the connection plate 3 of the bumper stopper 1 are inevitably increased in proportion.